Fallacy

Thomas Blunderville (sic, Blundeville?), The Art of Logic (1599), quoted in Sister Miriam Joseph, The Trivium 200 (2002). Sister Miriam explains: "The second proposition is true with respect to the time while a man sleeps; he may sin when he is awake." But there seems to be something else going on here; wouldn't he sin not even if he slept badly, so long as he slept.